So, what is up in this video? Does the hippo really show evidence of empathy for the impala? Or is he stealing the croc's lunch out of curiosity only to find that he doesn't like impala, remembering he is an herbivore?

If we assume empathy is at play, then this is an extreme version of it. Nature is full of altruistic examples, at least between members of the same species. Between species there are also cases of you scratch my back and I'll scratch yours. Obviously, this example is different. Why did the hippo attempt to rescue the impala? Do hippos have morals?

Is man flu better or worse than bird flu? (Note the implications for man-made vs. other-animal-made (aka "natural") pestilence on the earth in your reply). Either way, I hope you get to feeling better soon.

There are two separate events in this behavioral sequence:1- the hippo chased the crocodile.2- the hippo interacts with the agonizing impala. the most parsimonious explanation for event 1 is that hippos don't usually tolerate crocodiles in their territories, mostly because they're a threat to their offspring. There is no need to postulate any kind of altruism in this action. If anything, the struggle just attracted the hippo's attention.Event 2 can be explained in the following way: hippos don't appreciate decomposing bodies in their pool (they don't know what they're missing!)and they tend to clean up their territories. So the hippo takes the body to the shore, only to find it it still moving. Now that's intriguing! Usually hippos can't get close enough to live impalas to actually touch them. So this interesting object is investigated, using the mouth which is really the only organ hippos can use to investigate anything... Again, postulating "an attempt to revive the impala" is not the most parsimonious explanation.

Thanks for the comment, Nicholas! You've caught me doing that thing I'm all too guilty of -- anthropomorphizing Hippo behavior. I'll get back to criticizing other humans' anthropomorphizing their deities once I get this log out of my eye.

Well said Nicholas! I would most likely agree with that. An alternative however is IF the hippo is a female she may have had the maternal instinct to protect the impala. There have been numerous examples of maternal instincts of species causing such interactions. It did appear to be very gentle with the impala so I feel it's a possibility. Also because hippos are one of the more intelligent species, its curiosity may have also helped in the unusual behavior because like you said its not everyday a hippo can get that close to an impala.